Liquid crystal display panel and color filter

ABSTRACT

A manufacturing method of a color filter including following steps is provided. First, a partition is formed on a substrate to form a plurality of pixel regions on the substrate. Next, a color pigment is provided along a continuous pigment-providing route, so as to form the color pigment on a sequence of pixel regions among the plurality of pixel regions and the partition. The method mentioned above can prevent the unfilled phenomenon of the pigment around the corners of the pixel region. Besides, a liquid crystal display panel having the color filter is also provided.

CROSS-REFERENCE TO RELATED APPLICATION

This application is a divisional of and claims the priority benefit ofU.S. application Ser. No. 11/944,415, filed on Nov. 22, 2007, nowallowed, which claims the priority benefit of Taiwan application serialno. 96127943, filed on Jul. 31, 2007. The entirety of each of theabove-mentioned patent applications is hereby incorporated by referenceherein and made a part of this specification.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a display device and a manufacturingmethod thereof, and more particularly to a liquid crystal display (LCD)panel, a color filter, and a manufacturing method thereof.

2. Description of Related Art

Generally, in a manufacturing method of color filter for a common LCD,RGB photo resists are adopted to be processed by three photolithographyprocesses, and three color photo resist films are sequentially formed inpixels on a substrate, thereby forming a color filter. The color photoresist films are formed by dripping the photo resist liquid on thesubstrate and then spin-coating the photo resist liquid on the substrateuniformly. As a result, most of the color photo resist is wasted duringthe spin-coating process, and furthermore, the photo resist isexpensive, thereby causing a high manufacturing cost. In addition, theadopted photolithography processes require plenty of organic solvent,which possibly causes environmental contamination.

Recently, a method of forming a color filter by using an inkjet printing(IJP) process has been developed. The method includes the followingsteps, firstly, forming a black matrix with a plurality of openings on asubstrate; then, dripping color pigments (red, green, and blue) into theopenings of the black matrix by using an inkjet print head; and thenperforming a thermal baking process to cure the pigments, therebyforming a color filter. The inkjet printing method can simultaneouslyinkjet print RGB filter films in pixels, and significantly save themanufacturing processes and the material cost compared with theconventional photolithography processes adopted in manufacturing thecolor filter, so that the inkjet printing technology has an advantage ofbeing manufactured in a large area.

Generally speaking, when the color filter is manufactured by using theinkjet printing technology, it is expected that all color pigments aredripped completely in pixel regions, so as to prevent the color pigmentsfrom overflowing or being mixed with each other. Therefore, theconventional process of dripping the color pigments in a pixel regionrequires that the positions of the first drop and the last drop of thecolor pigments in a pixel region are kept a certain distance away fromthe edge of the pixel region. In this manner, if the position where thecolor pigment is dripped is slightly inaccurate, the color pigment maybe prevented from overflowing the pixel region to be mixed with otherpigments. However, although such an inkjet printing method is capable ofpreventing the color pigments from overflowing or being mixed with otherpigments, if the pixel region has a poor hydrophile property or thepixel region is too large, the unfilled phenomenon of the color pigmentpossibly occurs at the corners of the pixel region, and as a result, anLCD panel has a poor color saturation and poor displaying quality.

SUMMARY OF THE INVENTION

Accordingly, the present invention provides a method of manufacturing acolor filter, capable of preventing the unfilled phenomenon fromoccurring at an edge of a pixel region.

Through the aforementioned manufacturing method, the present inventionfurther provides a color filter with high quality.

The present invention further provides an LCD panel employing the colorfilter and having desirable color saturation.

The present invention further provides an ink jetting apparatus, whichis suitable for being used in a manufacturing process of the colorfilter, so as to manufacture a color filter with a desirable quality.

In order to further describe the content of the present invention indetail, the present invention provides a method of manufacturing a colorfilter, which includes the following steps, firstly, providing asubstrate and forming a partition on the substrate, so as to form aplurality of pixel regions on the substrate; then, providing a colorpigment in a continuous pigment-providing route, so as to form the colorpigment on a sequence of pixel regions among the plurality of pixelregions and on at least a part of the partition.

In an embodiment of the present invention, the method further comprisesa step of providing another color pigment in another continuouspigment-providing route, so as to form another color pigment in anothersequence of pixel regions among the plurality of pixel regions and on atleast a part of the partition, in which the sequence of pixel regionsand another sequence of pixel region are adjacent to each other, forexample. Furthermore, the color pigment and another color pigment may beprovided simultaneously or sequentially.

In an embodiment of the present invention, the continuouspigment-providing route is a linear route or a zigzag route.

In an embodiment of the present invention, the process of providing thecolor pigment is to spray the color pigment on the substrate by using aninkjet print head, and the practical operation is to spray the colorpigment by means of, for example, moving the inkjet print head along thecontinuous pigment-providing route, moving the substrate along thecontinuous pigment-providing route, or moving the substrate and theinkjet print head with respect to each other along the continuouspigment-providing route.

In an embodiment of the present invention, the color pigment may befurther cured to form a color filtering material.

In an embodiment of the present invention, the thickness of the colorfiltering material on at least a part of the partition is approximatelylarger than 0 μm and smaller than or equal to 0.4 μm.

In an embodiment of the present invention, the thickness of the colorfiltering material on at least a part of the partition is about 0.3 μm.

In an embodiment of the present invention, after forming the colorpigment, a conductive layer is further formed on the substrate.Furthermore, after forming the color pigment and before forming theconductive layer, a planarization layer is further formed on thesubstrate.

In an embodiment of the present invention, the method of manufacturingthe color filter further comprises providing a color pigment in asecondary continuous pigment-providing route, so as to form the colorpigment in a sequence of pixel regions among a plurality of pixelregions and on at least a part of the partition. The secondarycontinuous pigment-providing route is, for example, parallel to thecontinuous pigment-providing route, so as to provide a color pigment inthe same pixel region.

The present invention provides a color filter, which includes asubstrate, a partition, and at least one color filtering material. Thepartition is disposed on the substrate, so as to form a plurality ofpixel regions. The color filtering material is located in at least onesequence of the pixel regions among the plurality of pixel regions andon at least a part of the partition.

In an embodiment of the present invention, the thickness of the colorfiltering material on the partition is approximately larger than 0 μmand smaller than or equal to 0.4 μm.

In an embodiment of the present invention, the thickness of the colorfiltering material on the partition is about 0.3 μm.

In an embodiment of the present invention, the at least one colorfiltering material is a red pigment, a green pigment, a blue pigment, ora combination thereof.

In an embodiment of the present invention, the pixel regions arearranged in an array or in a mosaic manner.

In an embodiment of the present invention, the at least one sequence ofpixel regions are arranged in a straight line or a zigzag shape.

In an embodiment of the present invention, the color filter furtherincludes a conductive layer located on the partition and at least onecolor filtering material.

In an embodiment of the present invention, the color filter furtherincludes a planarization layer located below the conductive layer andused for covering the partition and at least one color filteringmaterial.

In an embodiment of the present invention, the color filter furtherincludes a hydrophobic layer on the partition.

The present invention provides an LCD panel, which includes an arraysubstrate, a color filter, and a liquid crystal layer. The color filterincludes a substrate, a partition, and at least one color filteringmaterial. The partition is disposed on the substrate, so as to form aplurality of pixel regions on the substrate. At least one colorfiltering material is located in at least one sequence of pixel regionsamong the plurality of pixel regions and on at least a part of thepartition. The liquid crystal layer is sandwiched between the arraysubstrate and the color filter.

The present invention provides an ink-jetting apparatus, which includesa first inkjet print head, a second inkjet print head, and a connectingmeans. The first inkjet print head has a row of first nozzles, and thesecond inkjet print head has a row of second nozzles. The row of firstnozzles and the row of second nozzles are arranged alternately. Theconnecting means is disposed between the first inkjet print head and thesecond inkjet print head to connect the first inkjet print head with thesecond inkjet print head.

In an embodiment of the present invention, the ink-jetting apparatusfurther includes a third inkjet print head and another connecting means.The third inkjet print head has a row of third nozzles, and the thirdnozzles of the third inkjet print head and the second nozzles of thesecond inkjet print head are arranged alternately. Another connectingmeans is disposed between the third inkjet print head and the secondinkjet print head to connect the third inkjet print head with the secondinkjet print head.

In an embodiment of the present invention, the connecting means is anadhesive.

In the method of manufacturing a color filter provided by the presentinvention, the color pigment is sprayed along the continuouspigment-providing route, thereby preventing the unfilled phenomenon ofthe color pigment in the conventional technology from occurring to thecorners of a pixel region and further enhancing the quality andproduction yield of the color filter.

In order to make the aforementioned and other objects, features, andadvantages of the present invention comprehensible, embodimentsaccompanied with figures are described in detail below.

It is to be understood that both the foregoing general description andthe following detailed description are exemplary, and are intended toprovide further explanation of the invention as claimed.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings are included to provide a furtherunderstanding of the invention, and are incorporated in and constitute apart of this specification. The drawings illustrate embodiments of theinvention and, together with the description, serve to explain theprinciples of the invention.

FIGS. 1A to 1D are schematic views of a process for manufacturing acolor filter according to an embodiment of the present invention.

FIG. 2 is a schematic view of two nozzles for providing color pigment tothe same sequence of the pixel regions simultaneously.

FIG. 3 is a schematic view of spraying the color pigment on one sequenceof the pixel regions and another sequence of the pixel regionssimultaneously.

FIG. 4 is a schematic view of an ink-jetting apparatus according to anembodiment of the present invention.

FIG. 5 is a schematic view of spraying the color pigment by using theink jetting apparatus in FIG. 4.

FIG. 6 is a schematic sectional view of a color filter according to anembodiment of the present invention.

FIGS. 7A and 7B are schematic views of pixel regions arranged in anarray.

FIGS. 7C and 7D are schematic views of the pixel regions arranged in amosaic manner.

FIG. 8 is a schematic view of an LCD panel according to an embodiment ofthe present invention.

DESCRIPTION OF EMBODIMENTS

FIGS. 1A to 1D are schematic views of a process for manufacturing acolor filter according to an embodiment of the present invention.Referring to FIG. 1A, firstly, a substrate 100 is provided, and thematerial of the substrate 100 is, for example, a transparent rigidsubstrate, such as glass. Then, a partition 120 is formed on thesubstrate 100, so as to form a plurality of pixel regions 122 on thesubstrate 100. In an embodiment, the partition 120 may be a materialwith a low light transmittance and a small reflectance, such as anopaque metal film and a resin having a black dye, or the opaque metalfilm and the resin having a black dye are both used simultaneously.

Furthermore, in order to prevent the subsequently-spayed color pigmentsfrom overflowing or being mixed with each other, a hydrophobic treatmentmay be further performed on the partition 120. As shown in FIG. 1B, thehydrophobic treatment may be performed on the surface of the partition120 by using a fluoride-containing plasma, so as to form a hydrophobiclayer 124 or hydrophobic surface on the partition 120. The gas sourcefor forming the fluoride-containing plasma is, for example, CF₄, SF₆, oranother fluoride-containing gas. Of course, besides performing thehydrophobic treatment on the surface of the partition by using thefluoride-containing plasma, a hydrophobic layer 124 may be additionallyformed on the partition 120 by means of deposition after the partition120 is formed, or the partition 120 is made to have the hydrophobicproperty through another existing process.

Referring to FIG. 1C, a color pigment 140 a is provided in a continuouspigment-providing route L1, so as to form the color pigment 140 a in asequence of pixel regions 122 among the plurality of pixel regions 122and on the partition 120. Particularly, in this embodiment, the colorpigment 140 a is sprayed on the plurality of pixel regions 122 on thesubstrate 100 along the continuous pigment-providing route L1 by movingan inkjet print head 130. Furthermore, the relative position between theinkjet print head 130 and the substrate 100 can also be controlled bymoving the substrate 100 or moving the substrate 100 and the inkjetprint head 130 with respect to each other, so as to spray the colorpigment 140 a in the pixel regions 122.

It should be mentioned that, the inkjet print head 130 provides thecolor pigment 140 a along the continuous pigment-providing route L1,i.e., the color pigment 140 a is continuously provided along thecontinuous pigment-providing route L1. Therefore, the color pigment 140a is left above the pixel regions 122 and on at least a part of or allof the partition 120, as shown in FIGS. 1C and 1D. In this way, theunfilled phenomenon of the color pigment 140 a does not easily occur atthe corners of each pixel region 122. Furthermore, since the inkjetprint head 130 continuously provides the color pigment 140 a when itmoves above the partition 120, and the partition 120 has the hydrophobicproperty, only a part of the color pigment 140 a is left on thepartition 120, which does not cause the color pigment 140 a to overflowor to be mixed up. In an embodiment, the color pigment 140 a may befurther cured, so as to form a color filtering material 140 in the pixelregions 122. In this embodiment, the thickness of the color filteringmaterial 140 on the partition 120 is approximately in a range from 0 μmto 0.4 μm, preferable about 0.3 μm.

Besides using the same nozzle to provide the color pigment to a sequenceof pixel regions, two or more nozzles may also be used to provide thecolor pigment to the same sequence of pixel regions. FIG. 2 is aschematic view of using, for example, two nozzles to provide the colorpigment to the same sequence of the pixel regions simultaneously.Referring to FIG. 2, the inkjet print head 130 includes two nozzles 132for providing the color pigment 140 a to the same sequence of pixelregions 122 a and at least a part of partition 120 simultaneously alongthe continuous pigment-providing route L1 and the secondary continuouspigment-providing route L2. In this manner, if the area of the pixelregions 122 is too large, two or more than two nozzles 132 can be usedto provide the color pigment 140 a to the same sequence of pixel regions122 a simultaneously. Therefore, the unfilled phenomenon of the colorpigment 140 a can be effectively prevented from occurring at the cornersof the pixel regions 122, and the manufacturing rate can be enhanced.

Besides the above ink-jetting manner, another color pigment is furtherprovided in another continuous pigment-providing route. Referring toFIG. 3, a first inkjet print head 130 r, a second inkjet print head 130g, and a third inkjet print head 130 b adopted herein are parallel toeach other, so that a first nozzle 132 r, a second nozzle 132 g, and athird nozzle 132 b are used to provide a first color pigment 140 r, asecond color pigment 140 g, and a third color pigment 140 b in a first,second, and third sequences of pixel regions 122 r, 122 g, and 122 bsimultaneously. Particularly, the first inkjet print head 130 r providesthe first color pigment 140 r along the first continuouspigment-providing route Lr, the second inkjet print head 130 g providesthe second color pigment 140 g along the second continuouspigment-providing route Lg, and the third inkjet print head 130 bprovides the third color pigment 140 b along the third continuouspigment-providing route Lb. In this manner, the first, second, and thirdcolor pigments 140 r, 140 g, and 140 b are respectively formed in thefirst, second, and third sequences of pixel regions 122 r, 122 g, and122 b, and at least a part of or all of the partition 120. The first,second, and third sequences of pixel regions 122 r, 122 g, and 122 bare, for example, adjacent to each other. The first, second, and thirdcolor pigments 140 r, 140 g, and 140 b are, for example, a red pigment,a green pigment, a blue pigment, or any combination thereof.

Besides the ink-jetting method shown in FIG. 3, in the presentinvention, through the design of the inkjet print head, different colorpigments are sequentially provided to the different sequences of pixelregions. FIG. 4 is a schematic view of an ink jetting apparatusaccording to an embodiment of the present invention. Referring to FIG.4, the ink jetting apparatus 400 includes the first inkjet print head130 r, the second inkjet print head 130 g, the third inkjet print head130 b, a connecting means 440, and another connecting means 450. Theconnecting means 440 and the connecting means 450 are, for example,adhesive or locking elements. The first inkjet print head 130 r has arow of first nozzles 132 r, the second inkjet print head 130 g has a rowof second nozzles 132 g, and the third inkjet print head 130 b has a rowof third nozzles 132 b. The first nozzles 132 r of the first inkjetprint head 130 r and the second nozzles 132 g of the second inkjet printhead 130 g are arranged alternately, and the second nozzles 132 g of thesecond inkjet print head 130 g and the third nozzles 132 b of the thirdinkjet print head 130 b are arranged alternately. Furthermore, theconnecting means 440 is disposed between the first inkjet print head 130r and the second inkjet print head 130 g, so as to connect the firstinkjet print head 130 r to the second inkjet print head 130 g.Similarly, the connecting means 450 is disposed between the secondinkjet print head 130 g and the third inkjet print head 130 b, so as toconnect the second inkjet print head 130 g to the third inkjet printhead 130 b. In this manner, the ink-jetting apparatus 400 maysequentially spray the color pigments on the sequences of pixel regions,so as to spray color pigments on a pixel region array with a large area,and thereby enhance the production efficiency.

FIG. 5 is a schematic view of spraying the color pigments by using theink jetting apparatus. Referring to FIG. 5, the row of first nozzles 132r, the row of second nozzles 132 g, and the row of third nozzles 132 bsequentially provide the first color pigments 140 r, the second colorpigments 140 g, and the third color pigments 140 b to the first, second,and third sequences of pixel regions 122 r, 122 g, and 122 b. The first,second, and third inkjet print heads 130 r, 130 g, and 130 b provide thefirst, second, and third color pigments 140 r, 140 g, and 140 b alongthe first, second, and third continuous pigment-providing routes Lr, Lg,and Lb, respectively. Particularly, since the row of first nozzles 132r, the row of second nozzles 132 g, and the row of third nozzles 132 bare arranged alternately, when the first nozzles 132 r begins to providethe first color pigment 140 r to the first sequence of pixel regions 122r, the second nozzles 132 g does not begin to provide the second colorpigment 140 g to the second sequence of pixel regions 122 g yet;similarly, when the second nozzles 132 g begins to provide the secondcolor pigment 140 g to the second sequence of pixel regions 122 g, thethird nozzles 132 b does not begin to provide the third color pigment140 b to the third sequence of pixel regions 122 b. That is, threeinkjet print heads 130 r, 130 g, and 130 b sequentially provide threecolor pigments 140 r, 140 g, and 140 b to the three sequences of pixelregions 122 r, 122 g, and 122 b. The method of spraying color pigmentsby using such an ink-jetting apparatus is suitable for spraying a pixelregion array with a large area, thereby further enhancing the productionefficiency.

FIG. 6 is a schematic sectional view of a color filter according to anembodiment of the present invention. The color filter 600 includes asubstrate 610, a partition 620, and at least one color filteringmaterial 640. The partition 620 is disposed on the substrate 610, so asto form a plurality of pixel regions 622 on the substrate 610. The colorfiltering material 640 is located in at least one sequence of pixelregions 622 among the plurality of pixel regions 622 and on thepartition 620. The color filtering material 640 may be a red pigment, agreen pigment, a blue pigment, or a combination thereof. Since the colorfiltering material 640 is sprayed on a sequence of pixel regions 622along the continuous pigment-providing route, the unfilled phenomenon ofthe color filtering material 640 does not occur easily at the corners ofeach pixel region 622. Furthermore, since the color filtering material640 is sprayed along the continuous pigment-providing route, the colorfiltering material 640 is also left on the partition 620.

Referring to FIG. 6, the color filter 600 further includes aplanarization layer 630 and a conductive layer 650. The conductive layer650 is located on the partition 620 and the color filtering material640, so as to serve as a common electrode of the color filter 600. Theplanarization layer 630, located below the conductive layer 650, coversthe partition 620 and the color filtering material 640. Furthermore, thecolor filter 600 further includes a hydrophobic layer 624 on thepartition 620, so as to prevent the sprayed color pigments fromoverflowing and being mixed up. Furthermore, the hydrophobic layer 624may be formed as follows, for example, performing the hydrophobictreatment on the surface of the partition 620 by usingfluoride-containing plasma or forming a hydrophobic layer 624 on thepartition 620 by means of deposition.

Furthermore, the continuous pigment-providing routes may be adjusteddepending upon the different arrangement manner of the pixel regions.FIGS. 7A and 7B show the pixel regions arranged in an array. FIGS. 7Cand 7D show the pixel regions arranged in a mosaic manner. Particularly,the pixel regions 722 arranged in an array or in a mosaic manner includesub-pixel regions of three different colors, for example, red sub-pixelregions 722 r, green sub-pixel regions 722 g, and blue sub-pixel regions722 b. In FIGS. 7A, 7C, and 7D, the red, green, and blue sub-pixelregions 722 r, 722 g, and 722 b in the sequence are arranged into azigzag shape, so that the first, second, and third continuouspigment-providing routes Lr, Lg, and Lb are designed as zigzag routes.In FIG. 7B, the red, green, and blue sub-pixel regions 722 r, 722 g, and722 b in the sequence are arranged in a straight line, so that thefirst, second, and third continuous pigment-providing routes Lr, Lg, andLb are designed as linear routes.

FIG. 8 is a schematic view of an LCD panel according to an embodiment ofthe present invention. Referring to FIG. 8, the LCD panel 800 includesan array substrate 810, a color filter 820, and a liquid crystal layer830. The color filter 820 and the array substrate 810 are disposedfacing each other, and the liquid crystal layer 830 is sandwichedbetween the array substrate 810 and the color filter 820. It should bementioned that, the color filter 820 adopted herein is, for example, thecolor filter 600 mentioned in the above embodiment, or the color filtermanufactured by using the above methods, which is not limited here.

In view of the above, the ink jetting apparatus, the LCD panel, thecolor filter, and the manufacturing method thereof provided by thepresent invention have the following advantages.

1. The color pigments are sprayed along the continuous pigment-providingroutes. Therefore, compared with the conventional method, the unfilledphenomenon of the color pigments does not easily occurs at the cornersof the pixel regions, thereby enhancing the quality and production yieldof the color filter. Furthermore, the LCD panel using the color filtermanufactured by the above method has desirable color saturation andsuperior displaying quality.

2. As for the ink jetting apparatus provided by the present invention,the first nozzles, the second nozzles, and the third nozzles of the inkjetting apparatus are arranged alternately, the relative positionsthereof are fixed by the connecting means, so that the color pigmentsare sequentially sprayed on the sequences of pixel regions, which can beapplied on a pixel region array with a large area and thus enhances theproduction efficiency.

It will be apparent to those skilled in the art that variousmodifications and variations can be made to the structure of the presentinvention without departing from the scope or spirit of the invention.In view of the foregoing, it is intended that the present inventioncover modifications and variations of this invention provided they fallwithin the scope of the following claims and their equivalents.

1. A color filter, comprising: a substrate; a partition disposed on thesubstrate to form a plurality of pixel regions on the substrate; and atleast one color filtering material, located in at least one sequence ofpixel regions among the plurality of pixel regions and on at least apart of the partition, wherein the thickness of the color filteringmaterial on the at least a part of the partition is larger than or equalto 0.3 μm, and smaller than or equal to 0.4 μm.
 2. The color filter asclaimed in claim 1, wherein the pixel regions are arranged in an arrayor in a mosaic manner.
 3. The color filter as claimed in claim 1,further comprising a conductive layer located on the partition and theat least one color filtering material.
 4. The color filter as claimed inclaim 3, further comprising a planarization layer, located below theconductive layer, for covering the partition and the at least one colorfiltering material.
 5. The color filter as claimed in claim 1, furthercomprising a hydrophobic layer on the partition.
 6. A liquid crystaldisplay (LCD) panel, comprising: an array substrate; a color filter,comprising: a substrate; a partition disposed on the substrate to form aplurality of pixel regions on the substrate; and at least one colorfiltering material, located in at least one sequence of pixel regionsamong the plurality of pixel regions and on at least a part of thepartition, wherein the thickness of the color filtering material on theat least a part of the partition is larger than or equal to 0.3 μm, andsmaller than or equal to 0.4 μm; and a liquid crystal layer, sandwichedbetween the array substrate and the color filter.